As explained in the mod infographics, researching the alchemical herbs requires Eorzean Seed Stock, a research bench attachment that can only be obtained from certain Eorzean caravans and settlements.

Is the requirement not showing up on the research project tooltips themselves?

That makes sense, I don't see those listed on the tool tips for the research. Here's a screen shot of one of the researches I debug finished (https://imgur.com/a/gQLCxF2). I also use Owlchemist's research tree so that might be the issue with the tool tip?

The vanilla research project details pane shows that it is required[cdn.discordapp.com], but if modded research tree views have problems surfacing these requirements, then I'll about adding it to each individual tooltip.